I recently purchased a used 2009 Civic Hybrid with 22k miles on it. Since then, I've averaged about 32 mpg (according to the display gauge). My hand calculated shows that to be accurate within about 1-2 mpg.

I use odometer setting B to gauge every tank of gas. When I fill up, I tend to read around 40 mpg around the first few miles. Then it drops to about 32 mpg with a couple bars left on the gas tank. I then refill the gas and start over. My overall mpg reads about 34 read not (on odometer setting A which has logged about 1200 miles since I purchased it). I'm trying to figure out why I cannot stay at least near 40 mpg consistently.

I've noticed a couple issues that are worth mentioning.

I only get to about 40 mph when I started resetting my tires to 40 psi (done at gas fill up). I think there is a slow leak in one tire which seems to drop to 30 psi before the next tank of gas. Would decreasing psi in one tire (or unevenness in psi) cause this low of a mpg? I took it to Honda and they told me that all of my gas sensors on the tires have a slow leak and should be replaced. I'm thinking about doing it but they are going to charge $450. Has anyone had a problem with the sensors leaking?

It has been 90-105 here the last few weeks so I have been running the AC constantly on high. It doesn't cool well in city traffic which I see may have been a known problem for the cars. Could the AC be responsible for a 10 mpg drop?

Thanks for any comments. I'm new to hybrids and have read tutorials about hypermiling but I think I have more basic problems than need to be solved.

07-09-2012 05:44 AM

HCHTimes2

I too just bought a 2009

I too just bought a 2009 HCH, this one with 31k miles. I traded a 2004 HCH which was getting around 40 mpg at 145k miles with running the air regularly (its been 100+ here for weeks). I have also noticed that I am only getting low 30's with the 2009, in addition to the infamous regen issues with the IMA battery where it charges and discharges quickly, resulting in zero assist. Having HCH and Insight experience, I know how to coax these Honda Hybrids correctly for max MPG, but so far, snake eyes on this 2009.

Obviously the previous owner had the software upgrade done before they traded it; are there any NEW software patches from Honda that fixes this problem? I'd hate to have to wait for the IMA to fail to have this issue addressed by Honda. It's a shame, its a really nice car (leather and navi model), but my old HCH seems to be the better car. Plus the acceleration in the 2009 is downright dismal in comparison to the 2004.

JCLEARY: The PSIs might help a little, but its possible your 2009 also had the software patch work done to it which decreases the MPG. Check the IMA battery guage and note if its charging and discharging rapidly.

07-09-2012 06:09 AM

jcleary

Hi and thanks for the

Hi and thanks for the response.

I suspect the software patch was completed because it does seem to discharge rapidly, although that is subjective since I don't know what it would be like before. I can get it to fully charge on the highway, but then discharge within a minute or two of going up and down hills.

So if the software patch was done, does that mean we are stuck with mpg in the low 30s?

07-11-2012 04:58 AM

HCHTimes2

Hello --
Yeah, it sounds

Hello --

Yeah, it sounds like yours had the software patch done before you acquired it. As a means of comparison, my 2004 took longer to charge when low, but also lasted MUCH longer when going up hills or when using assist to merge into traffic, etc. I find my 2009 charges too fast, discharges way too fast, and then fails to provide electric assist to the gas engine. It also fails to go into auto stop when the battery is low, which is often. FYI, my 2004 never failed to provide assist; the battery even got down to 1 bar and still I had assist...and it also never failed to auto stop at a light unless the defroster was on.

My GF has a 2010 Insight and she has no such issues. Hers charges and discharges as my 2004 Civic Hybrid did, no problems, and gets 42 mpg all day long, even before she "knew" how to drive it to max MPG. In fact her car is also more responsive and brakes much better. My 2009 is almost dangerous when coming from a stop; the acceleration without assist is non existent.

I have been researching the patch to see what the options are. So far, I haven't seen any fixes for this problem. I really wish I'd researched this before I pulled the trigger! I just figured it would be at least as good as a car as my first Civic Hybrid except with the bells and whistles of a more upscale car. Now I see why someone traded it at 31k miles and how come it looks brand new.

07-11-2012 06:45 AM

jcleary

Since I last filled the tank

Since I last filled the tank and tires (40 psi), I have tried to keep my rpm to under about 2500 or approaching 3000 at most when needing to speed up for on ramps or something else. Since then, I've pushed my mpg to about 40 now. It was surprising that I would really have to work at it just to achieve 40 mpg to me.

Also I still have to replace the tire pressure sensors they apparently were causing a leak. Has anyone else seen that happening?

07-16-2012 07:53 AM

Recommendations for Insight

Recommendations for Insight alternatives will never be complete without mention of the Toyota Prius. Certainly the standard of everything the Insight and Civic hybrids have tried to be, the Prius touts an aerodynamic, drag-reducing exterior. wrongful death lawyers

07-18-2012 04:07 PM

ON THE TIRE PRESSURE

ON THE TIRE PRESSURE MONITORS GO TO A REPUTABLE TIRE SHOP THE VALVE STEMS ARE AVALIBLE FOR REPLACEMENT ON MOST SENSORS FOR MAYBE 25.00 EACH INC LABOR. TRY THAT ROUTE BEFORE GOING TO THE WONDERFUL DEALER

07-19-2012 12:33 AM

check this thread

check this thread out....2009 Honda Civic battery problem

08-11-2012 01:59 AM

HCHTimes2

UPDATE: After trying to

UPDATE: After trying to persuade the selling dealership to take the car back with literally no progress, I decided to craft a very detailed letter for the Honda sevice department outlining the problem. I took the car in on Tuesday.

I got a call that afternoon that the dealership was able to duplicate the problem, they pulled the code from the computer (Note: the IMA light was NOT/NOT on) and they discovered an "internal battery error" for the IMA battery, code p1448. They didnt hesitate to order a new one and replaced it. I had my car back in 2 days; today was my first full day driving it.

WOW. It's a totally different car! Reliable, sustained assist, MPG is up, no stuttering or near stalls. I was able to eek out 37 mpg before the fix, so I am cautiously optimistic that I'll be able to get this one to where my 2004 was..low to high 40's.

08-23-2012 05:36 AM

jcleary

HCHTimes2:
Wow so it sounds

HCHTimes2:
Wow so it sounds like everything kind of worked out for you! So with the new battery are you able to stay in the 40's without much work?

It sounds like I never had the battery problems that you did. I have been learning how to drive the 09' HCH better am now able to get about 40 mpg on most tanks of gas. To do so still requires what I think is a large amount of effort on my part. I think the average person just choosing to drive my car would cause the mpg to plummet to around 30.

I was just wondering what the specified 40city/45 highway actually means. Is that some type of average Honda comes up with or is that number based at least someone that has knowledge of basic hypermiling?